Chromega Dichoric Filters

Discussion in 'Enlarging' started by Bruce Osgood, Oct 28, 2003.

  1. Bruce Osgood

    Bruce Osgood Membership Council Council

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    I recently purchased a used Omega D55 with Chromega color head. I've been using a Beseler 23 C dichoric for B/W printing. Both the Beseler and Chromega are noted in paper data sheets that Kodak CC filters are the equilivant and Magenta 200 equals a grade 5.

    However, the Chromega Magenta filter only goes to M-171. The Durst filter valuses go to 170.

    Can somebody enlighten me: DOES CHROMEGA USE THE KODAK OR DURST FILTERING VALUES?
     
  2. Aggie

    Aggie Member

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  3. Robert

    Robert Member

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    It's a USA enlarger. I'll lay dollars to donuts it's using Kodak standard numbers. Having said that. Haven't all the companies changed things over the years?

    Personally I'd suggest trying to calibrate it.
     
  4. Ed Sukach

    Ed Sukach Member

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    Ah ... a spin into the twilight zone. What paper/s are you using? Ilford *suggests* (n.b. "suggests") either single or dual dichroic head settings, and they just are not the same.

    Many moons ago I was became dissatisfied with the table giving the dichro filter settings, or more properly, the results they gave. I obtained the Ilford gelatin filter set (#0, 1/2, 1, etc.,) and with a lot of patience found that the fitration through the filters did *NOT* look much like the numbers in either table.

    I plotted new curves, matching the filters ... and ... success!!!

    I am convinced that there must be a LOT of variablity, enlarger-filter-set to enlager-filter set. I could give you *my* results - but I am not sure (seriously not sure) that they would fit your enlarger.

    In NO case did the filtration exceed the capacity of the D5500 head ... If I remember correctly, the highest numbers I saw were in the 150's.
     
  5. Tom Duffy

    Tom Duffy Member

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    I use a Super Chromega E (5x7). The Chromega uses kodak values. I haven't done extensive testing but I consider 10cc magenta to be equivalent to a grade 2 filter. If you want real 200 magenta, you'll have to use a suplementary magenta filter.
     
  6. Bruce Osgood

    Bruce Osgood Membership Council Council

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    Thank you Aggie, Robert, Ed and Tom. For my first working with the enlarger I used the White Light and no filter as a neutral point (Grade 2) and as much Magenta filter I 'feel' is correct.
    I've changed that to Low Light with no filter then about 100 M for the second exposure. It's working out: Time and Experience - there's no substitute. But thank you for your insights.
     
  7. Robert

    Robert Member

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    Are you doing spilt filtering? If so just crank the dials over. Max yellow for low contrast. Then no yellow and max magenta for hard contrast. I think that is right.
     
  8. Bruce Osgood

    Bruce Osgood Membership Council Council

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    Yes. But Max yellow (Y200) would be a very flat print, something like a grade 00. I think a neutral G2 is the absense of any filter and G5 would be the Max magenta, either M-170 with my enlarger or M-200 with something like the Beseler.
     
  9. Robert

    Robert Member

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    Wouldn't be any worse then using a green/blue filter. The final result is someplace in between.